# What Is Dequeue in Data Structure McQ?

//

Scott Campbell

A dequeue, also known as a double-ended queue, is a data structure that allows insertion and deletion of elements from both ends. It is similar to a queue and a stack combined, offering the flexibility of adding or removing elements from either end. In this article, we will explore the concept of dequeue in data structures and answer some multiple-choice questions related to it.

## Understanding Dequeue

A dequeue can be visualized as a linear collection of elements where both front and rear pointers are present. The front pointer refers to the first element of the dequeue, while the rear pointer refers to the last element. Elements can be inserted or removed at either end, making it highly versatile.

### Operations on Dequeue

The common operations performed on a dequeue include:

• Insertion at Front: This operation adds an element to the front of the dequeue.
• Insertion at Rear: This operation adds an element to the rear of the dequeue.
• Deletion from Front: This operation removes an element from the front of the dequeue.
• Deletion from Rear: This operation removes an element from the rear of the dequeue.

The ability to insert or delete elements from both ends makes dequeues suitable for various scenarios. For example, they can be used in algorithms that require efficient manipulation at both ends, such as implementing stacks, queues, or priority queues.

### Multiple-Choice Questions (MCQ)

Let’s test your understanding with some multiple-choice questions related to dequeues:

1. The term “dequeue” stands for:
1. Double Queue
2. Deletion Queue
3. Double-Ended Queue

2. Which of the following operations is NOT supported by a dequeue?
1. Insertion at Front
2. Insertion at Rear
3. Deletion from Front
4. Deletion from Middle

3. In a dequeue, elements are inserted and deleted from:
1. Only the front end
2. Only the rear end
3. Both the front and rear ends

### Solution to MCQs:

Question 1:
a) Double Queue
b) Deletion Queue
c) Double-Ended Queue

The correct answer is: c) Double-Ended Queue.

Question 2:
a) Insertion at Front
b) Insertion at Rear
c) Deletion from Front
d) Deletion from Middle

The correct answer is: d) Deletion from Middle.

Question 3:
a) Only the front end
b) Only the rear end
c) Both the front and rear ends

The correct answer is: c) Both the front and rear ends.

It’s essential to have a clear understanding of dequeues, as they form a crucial part of data structures. By mastering their operations and applications, you can efficiently solve problems that require dynamic insertion and deletion at both ends.

Hopefully, this article has provided you with a comprehensive overview of dequeues in data structures. Remember to practice implementing these operations to solidify your understanding.